Flashlight

ABSTRACT

Flashlight having an internal connector strip fixedly connected at one end to the flashlight lamp, and deflectable at the other end to make or break contact with a battery terminal. Contains provisions for maintaining accurate alignment between the deflector connector strip end and the battery terminal. The strip itself is so curved as to ensure reliable area contact with the battery terminal when deflected into its contact-making position.

limited States Patent 1191 I Kiider Sept. 10, 1974 [541 FLASHLIGHT 3,345,508 10/1967 .Chung 240/l0.65

4 1 [75] Inventor: Robert Koder, Ellwangen, Germany 3 4 3 084 5/ 969 Jammet 240/10 65 A v rt u h R FOREIGN PATENTS OR APPLICATIONS ssgnea a a lengese Sc 8 1 205 975 9/1970 Great Britain 240/10.65 Frankfurt/Mamfiermany 153,052 6/1932 Switzerland 240/6.4 R [22] Filed: Sept. 13, 1972 822,581 11/1951 Germany 1,528,584 5/1968 France [21] Appl. No.: 288,616 l,442,327 5/1966 France 271,770 8/1951 Switzerland [30] Foreign Application Priority Data Primary Exa'mmer ]oseph F. Peters, Jr.

Jan. 11, 1972 Germany, 2206544 Attorney Agent or Firm A1fred Stapler; Gerard J -W;K1L.S'.k 52 us. (:1. 240/10.65 pm [51] Int. Cl. ..'F21l7/00 57 ABSTRACT [58] Flew of Search 2.4O/ 1066 .Flashlight having an internal connector strip fixedly 240/10.6 R 6.4 R 2 S v v connected at one end to the flashlight lamp, and deflectable at the other end to make or break contact [56] References Cited with a battery terminal. Contains provisions for main- UNITED STATES PATENTS taining accurate alignment between the deflector con- 2,041,843 5/1936 Lifschitz 240/l0.65 nector strip end and the battery terminal. The strip it- 2,249,692 7/1941 self is so curved as to ensure reliable area contact with i322 the battery terminal when deflected into its contact- 2:697:297 12/1954 makmg posmon' 3,162,376 12/1964 17 Claims, 6 Drawing Figures FLASHLIGHT The invention relates to an improved flashlight, and particularly to an improved construction, and improved on-off switching means, for disposable flashlights susceptible of mass production.

It is known in the art to provide disposable flashlights comprising a battery chamber which contains a battery with positive and negative terminal blades and an upper portion or head, which houses the lamp and the on-off switching arrangement. In such known flashlights, it is predominantly the practice to establish conduction from the battery to the switch or lamp arrangement by means of two leaf springs, the configuration of the spring endings being such that, in cooperation with a switching device located outside the flashlight head, these flashlights are switched on or off.

Such arrangements have the drawback that the special curvature required by the negative terminal blade, which serves as both switching spring'and battery terminal, limits the applicability of automatic mounting of the lower portion, compared to what would be possible if the standard, flat battery terminal blades were utilized. In addition, precise positioning of the terminal blade is required, otherwise the position of the stop on the terminal blade does not line up with the limits of excursion of the switching device and reliable switching action is not assured.

Austrian Pat. No. 139,941 discloses an electrical pocket flashlight with replaceable batteries, whose housing, which is made of insulating material, contains both in its bottom and in its lid a spring-like metal strip. The one in the lid is connected directly to the lamp holder and is also connectible by means of a switching device to the free terminal of a battery or of an individual battery cell. The one in the bottom of the housing urges the battery or battery cells against the lamp or switch contact and also forms a connector bridging the various cells to one another.

Such a pocket flashlight is also not suitable for mass production, because even slight bending of the connector strip leads to a lack of contact surface, leaving only the possibility of an edgewise or lineal engagement.

A further disadvantage is that the strip used to conduct the battery current must have a very special curvature and, since there is no provision for maintaining a specific positional relationship to the other connector strip, firm and reliable contact-making is not assured.

Accordingly, it is an object of this invention to provide a flashlight which is suitable for mass production and in which firm connection to the lamp is assured.

This, and other objects which will appear are achieved by a flashlight arrangement having a battery chamber containing a battery with standard positive and negative terminal blades, and an upper or head portion attached (preferably non-detachably) to the battery chamber and containing the flashlight lamp, a resilient connector strip, or spring, and an on-off switch device. Reciprocating movement of the switch device. alternately urges the end of the connector spring into engagement with a battery terminal blade, or releases it from such engagement. The portion of thespring which thus engages the terminal blade is preferably in the form of a nearly closed loop, thus forming acurved surface reliably capable of area-contact with the battery blade.

-In accordance with this invention, the two terminal blades can be the kind conforming to [EC -3Rl2 DIN 40 868, which are susceptible of being mounted fully automatically and without any special shaping in the portion of the flashlight housing serving as the battery chamber.

For further details reference may be had to the following description in the light of the accompanying drawings wherein v FIG. 1 shows an elevation view, partly in crosssection, of a battery operated flashlight with both open and closed switch contacts;

FIG. 2'shows a bottom view of the flashlight head, including the switch connector spring, which simultaneously constitutes the lamp holder;

FIG. 3 is a top view of the battery operated flashlight without the slide switch;

FIG. 4 is an enlarged detailed view of the junction between the battery chamber and the flashlight head;

FIG. 5 is a bottom view of the flashlight head showing an alternate form of switch connector springs; and

FIG. 6 is a bottom view of just the switch connector spring, but in still another alternate form. V v

The same reference numerals are used in the differ ent figures to denote similar elements.

Referring now to FIG. 1, the battery operated flashlight consists of two main sub-assemblies.

One of these comprises the battery chamber 1, preferably made of plastic, which encloses battery cells 2, collectively provided in known fashion with a short positive terminal blade 3 and a longer negative blade 4. These terminal blades are preferably separated from the battery cells by an insulating flap 5 to preclude short-circuiting of the individual cells.

The other main sub-assembly, comprises the illuminating head 6, preferably made of plastic, and attached to chamber 1 in some suitable manner, such as the snap-in joint shown in.FIG. 4. The head 6 preferably has a sloping, narrow edge to which a switch 7 is attached. Optimal illuminating capability is achieved by a parabolic, highly polished reflective light emissive surface 9, at whose focal point lamp 10 is positioned.

As further appears from FIG. 1, the on and off positions of slide switch 7 are defined by two recesses 11 in its underside disposed transversely to the direction of sliding movement. These recesses 11 may be of hemispherical form, or in the form of slots of semicircular cross-section. At each extremity of the movement of slide 7 a resilient protuberance engages the appropriate recess 11, so that stable switch positions prevail.

FIG. 3 shows a U-shaped cut-out l6 defining a resilient plate at whose end the engaging protuberance 12 is positioned.

FIGS.,1 and 2 also show a connector spring 8, which is attached to the head by means of two blind rivets 13 and laterally guided by a vertical rib 14. The lower extremity of rib 14 also presses down on blade 3 of battery 2, so that reliable positioning of that blade relative to connector spring 8 is assured. If the lid is made of plastic, the rivets by means of which the connector spring 8 is attached to the upper portion may be heat setting bling rivets. This connector spring 8 is preferably under slight tension tending to urge its hook-shaped end away from engagement with terminal blade 3, and against stop 7a protruding inwardly into the flashlight head from slide switch 7. In the position of slide switch 7 and connector spring 8 shown in solid lines in FIG. 2, the hooked endof the spring is'out of contact with terminal blade 3, whereas movement of slide switch 7 to the position shown in broken lines depresses spring 8 into the positions also shown in broken lines, and establishes contact with terminal blade 3.

The connector spring 8 also serves as lamp holder for lamp l0, engaging the outer threaded portion of its base. On the other hand, the end terminal 15 of lamp 10 rests upon battery blade 4, thereby completing the electrical circuit connection within the flashlight.

As shown in- FIG. 4, attachment between battery chamber 1 and illuminating head 6 may be effected by means of mating corrugations l7 encircling the outer edge of the battery chamber and the inner edge of the illuminating head.

In constructing the flashlight-in question, the illuminating head portion is preferably molded of asingle piece of plastic, including the vertical rib 14. As shown in FIG. 2, for maximum strength that rib preferably extends all the way across the narrow interior width of the head position. However, near the bottom end, it has a vertical slot, for receiving the connector spring 8. This slot has to be narrow enough so that, at the bottom .end of the rib 14, its edges engage terminal blade 3 and hold that blade down, away frompossible unwanted engagement with spring 8. In order to fit within that narrow slot in rib 14, the connector spring 8 may have a narrowed-down mid-section 8a (see FIG. 2), in which it is not as wide as in the remainder of its length.

FIG. 5, to which reference may now be had, shows the adaptation of the invention to a bayonet-base flashlight lamp. For this form, the connector spring 8 again serves as the lamp holder, but, insteadof a threaded lamp receiving opening, it has a smooth opening with two diametrically opposed notches 8b and 80, through which to insert the lugs which protrude from a bayonettype lamp base. Also, azimuthally displaced from these notches 8b and 8c, there are depressions 8d and 82, for engaging the lugs in question, thereby retaining the lamp fixedly positioned within the holder formed by spring 8.

FIG. 8 shows still another lamp holder arrangement utilizing spring 8, this one being, as were FIGS. 1 and 2, for a threaded base lamp. In the arrangement of FIG. 6, the inner circumference of the lamp receiving aperture in opening 8 is formed into several azimuthally spaced protrusions such as 8f, 8g and 8h. Through theinherent resilience of spring 8, these protrusions yield somewhat when a lamp is pushed into that aperture and then engage the grooves in the threads of the base. By use of this arrangement, the lamp can be inserted by simply pressing it into the aperture in spring 8, without any need for twisting or turning. This is obviously advantageous for automated assembly. 1

Other modifications will also occur to those skilled in the art without departing from the inventive concept.

For example, although attachment of the connector spring by means of two rivets has been shown, the invention is not limited to that particular form. A single rivet, positioned between the lamp and the hooked end would also suffice. Likewise, the extension of spring 8 beyond the lampholder aperture would then not be necessary. Other conventional connector means between the battery chamber and the head portion of the flashlight may be provided, including some which permit disand reassembly of the flashlight. If a disassemblable arrangement is used, then the battery cells 2 need not necessarily be unreplaceable.

In order to utilize the largest possible parabolic reflector 9, the lamp 10 is preferably positioned as close to the center of the flashlight as the length of terminal blade 4 reasonably permits. In that case, however, it becomes possible to assemble the battery chamber and head portions with a rotation of one of them leading to the further possibility that the lamp may be constantly lit, or even cause a short circuit between the positive and negative battery terminal blades. This can be averted by either positioning the lamp far enough away from the hooked end of spring 8 so that even the above-mentioned 180 rotation has no adverse effect, or else constructing the flashlight housing in such a manner that assembly in mutually rotated positions is not feasible. The latter may be accomplished in any conventional manner, as, for example, by means of a tongue protruding vertically downward from the bottom edge of the head portion wall, and a notch in the battery chamber wall in such a position that the tongue and notch can mate only in the desired relative orientations. 5

Accordingly, it is desired that the invention be limited only by the appended claims.

I claim:

1. An on-off switching arrangement for a batteryoperated flashlight comprising:

a resilient connector spring positioned inside said flashlight, said connector spring having an end portion in the shape of a reentrant hook;

means for deflecting said spring so as to cause its said end portion to deflect between first and second positions, said end portion being out of contact with a terminal of said battery terminal in said first position and in contact with said terminal in said second position; and

means for laterally guiding said spring in its deflection between said positions, said guiding means restraining said spring from lateral displacement in its said deflection and consisting of a slot member open at one end, said spring being narrow enough to be received and deflected within said slot, and said slot being narrower than said terminal at said open end so that said member bears on said terminal at the open end of the slot to maintain said terminal in predetermined spaced relation to said first position.

2. The arrangement of claim 1 wherein said terminal is a resilient terminal blade of a multicell. battery.

3. The arrangement of claim 1 wherein the end of said spring opposite said hook end constitutes the lamp holder means for said flashlight.

4. The arrangement of claim 3 wherein said lamp holder means is in the form of an aperture in said spring for receiving the base of the flashlight lamp.

5. The arrangement of claim 4 wherein said aperture is in the shape of an internal thread for receiving a threaded lamp base.

6. The arrangement of claim 4 wherein said aperture has notches in its edge for the passage of the lugs on the base of a bayonet-type lamp.

7.'The arrangement of claim 4 wherein said aperture has an inner edge with azimuthally displaced resilient S protrusions deformable upon insertion of a threaded lamp base to engage the grooves of said thread.

8. The arrangement of claim 4 wherein said spring constitutes the electrical connector means between said base and said battery terminal.

9. The arrangement of claim 8 wherein the battery of said flashlight has positive and negative terminal blades confronting each other at the same end of the battery, said spring hook end establishing contact with one of said blades when deflected into said second position, and the center button of said lamp establishing contact with the other of said terminal blades when received within said spring aperture.

10. The arrangement of claim 1 further comprising a slide switch mounted on the outside of said flashlight and having a protrusion into the inside, said protrusion bearing on said hook end to produce deflection between said positions in response to displacement of said slide switch between two positions.

11. The arrangement of claim 10 further comprising detent means for maintaining said slide switch in either of said two displaced positions.

12. The arrangement of claim 11 wherein said detent means comprises at least one recess in the underside of said slide switch, and a resilient protruberance engaging said recess in one of said displaced positions.

13. The arrangement of claim 11 wherein the shape of said hook is such that said protrusion bears on a part of said hook forming a convex surface. I

14. The arrangement of claim 1 wherein said flashlight has two major subassemblies, one being the battery containing chamber and the other the illuminating head.

15. The arrangement of claim 14 further comprising means for preventing said head from being attached to said chamber except in one predetermined orientation relative to that of the chamber.

16. The arrangement of claim 14 comprising means for attaching resilient connector spring to the inside of said illuminating head so as to place said spring under tension urging it away from said battery chamber.

17. The arrangement of claim 16 wherein said connector spring is attached to said illuminating head by means of rivets, 

1. An on-off switching arrangement for a battery-operated flashlight comprising: a resilient connector spring positioned inside said flashlight, said connector spring having an end portion in the shape of a reentrant hook; means for deflecting said spring so as to cause its said end portion to deflect between first and second positions, said end portion being out of contact with a terminal of said battery terminal in said first position and in contact with said terminal in said second position; and means for laterally guiding said spring in its deflection between said positions, said guiding means restraining said spring from lateral displacement in its said deflection and consisting of a slot member open at one end, said spring being narrow enough to be received and deflected within said slot, and said slot being narrower than said terminal at said open end so that said member bears on said terminal at the open end of the slot to maintain said terminal in predetermined spaced relation to said first position.
 2. The arrangement of claim 1 wherein said terminal is a resilient terminal blade of a multicell battery.
 3. The arrangement of claim 1 wherein the end of said spring opposite said hook end constitutes the lamp holder means for said flashlight.
 4. The arrangement of claim 3 wherein said lamp holder means is in the form of an aperture in said spring for receiving the base of the flashlight lamp.
 5. The arrangement of claim 4 wherein said aperture is in the shape of an internal thread for receiving a threaded lamp base.
 6. The arrangement of claim 4 wherein said aperture has notches in its edge for the passage of the lugs on the base of a bayonet-type lamp.
 7. The arrangement of claim 4 wherein said aperture has an inner edge with azimuthally displaced resilient protrusions deformable upon insertion of a threaded lamp base to engage the grooves of said thread.
 8. The arrangement of claim 4 wherein said spring constitutes the electrical connector means between said base and said battery terminal.
 9. The arrangement of claim 8 wherein the battery of said flashlight has positive and negative terminal blades confronting each other at the same end of the battery, said spring hook end establishing contact with one of said blades when deflected into said second position, and the center button of said lamp establishing contact with the other of said terminal blades when received within said spring aperture.
 10. The arrangement of claim 1 further comprising a slide switch mounted on the outside of said flashlight and having a protrusion into the inside, said protrusion bearing on said hook end to produce deflection between said positions in response to displacement of said slide switch between two positions.
 11. The arrangement of claim 10 further comprising detent means for maintaining said slide switch in either of said two displaced positions.
 12. The arrangement of claim 11 wherein said detent means comprises at leaSt one recess in the underside of said slide switch, and a resilient protruberance engaging said recess in one of said displaced positions.
 13. The arrangement of claim 11 wherein the shape of said hook is such that said protrusion bears on a part of said hook forming a convex surface.
 14. The arrangement of claim 1 wherein said flashlight has two major subassemblies, one being the battery containing chamber and the other the illuminating head.
 15. The arrangement of claim 14 further comprising means for preventing said head from being attached to said chamber except in one predetermined orientation relative to that of the chamber.
 16. The arrangement of claim 14 comprising means for attaching resilient connector spring to the inside of said illuminating head so as to place said spring under tension urging it away from said battery chamber.
 17. The arrangement of claim 16 wherein said connector spring is attached to said illuminating head by means of rivets. 